AuthorTopic: Bonding perspex? (Read 1304 times)

Hi guys, im wanting to make a small box (12cm x 8cm) out of clear perspex 3mm thickness, it will be half filled with water, what glue do i use? Ive looked online and ive found some specialist glues but these are for making fishtanks and very expensive, i also read mixed comments that using superglue is fine on small projects which mine is but ive also read that i should not use super glue so would gorilla superglue (im thinking of the gel type) do the job? Or should i also put some silicone over the superglue from the inside when glue is set?

But beware, this not a glue like substance, it works by taking the solvent into the joint by capillary attraction and dissolving the joint faces to weld them together homogeneously. Therefore the mating surfaces of your box need to be very precise with close tolerances ( a few thou), the cement will not bridge a gap. Also use a hog hair bristle brush, any normal brush with nylon or plastic bristles will weld together to a blob.

Logged

The early bird catches the worm.But it is the second mouse that gets the cheese.

But beware, this not a glue like substance, it works by taking the solvent into the joint by capillary attraction and dissolving the joint faces to weld them together homogeneously. Therefore the mating surfaces of your box need to be very precise with close tolerances ( a few thou), the cement will not bridge a gap. Also use a hog hair bristle brush, any normal brush with nylon or plastic bristles will weld together to a blob.

For gap filling solvent cement you might try Tensol 12 which is basically Plastic Weld with acrylic dissolved in it. This will give a water tight join but you need to be careful you don't get stress fractures in the edges of the acrylic.

Logged

No human society has ever functioned without models to capture, explain,disseminate,persuade, sell, reinforce and analyse all kinds of ideas, values, concepts and situations.

Tizdaz. One trick I have heard about with perspex is id you run and cut edge which will be dull and cloudy is to run it over a open flame and it makes them clear again I think you can look this up on you-tube. Regards Howard.

UHU special plast working brilliant for me on the waterproof Perspex hatch assemblies on my Seabex build.A little thicker than normal solvent,100% waterproof and you keep optical carity provided you polish the edges up before gluing

I have seen reports of a possible problem on a laser cutting forum. Perspex sheet comes in two forms, cast or extruded. It seems that cut edges on extruded sheet can craze with some solvents or cleaners.

I have seen reports of a possible problem on a laser cutting forum. Perspex sheet comes in two forms, cast or extruded. It seems that cut edges on extruded sheet can craze with some solvents or cleaners.

Jim

Cast acrylic will craze as well as extruded. The solvent releases the internal stress in the plastic and small fractures occur at right angles to the edge. The cure is to anneal the plastic by baking it at 82 degrees (C) or 180 degrees (F) for one hour per millimetre of thickness and cooling for 2 hours this will prevent stress fracture when gluing.

Logged

No human society has ever functioned without models to capture, explain,disseminate,persuade, sell, reinforce and analyse all kinds of ideas, values, concepts and situations.